I wonder if the OP wasn't really asking what the difference between a programmable (or peripheral) interrupt controller and a memory control unit is. Maybe he's taking a course in computer architecture?
Otherwise, yeah, he's asking for the difference between apples and fruit.
I believe the name I heard was "periphreal interface controller" which makes more sense to me. But even then, I still remember reading that PIC didn't stand for anything...which doesn't make too much sense as who in marketing would pull "PIC" out of thin air?
Read the 'history" section of your wiki link. It seems to say there are many different contrived meanings for PIC, but that none of them are correct microchip calls them PICmicros as the brand name.
P*** I*** controller micro doesn't really make sense.
According to wikipedia, the original pic was made by general instruments and pic stood for "Programmable interface controller".
Edit, I see I was beaten to it.
I've been involved with PIC's for a LONG time, and the reasons for the name have been discussed many times over the years, and there's never really been any definative answer - if indeed it stood for anything?.
However, "periphreal interface controller" has usually been the most likely.
I was just looking around and found this data sheet for the pic1650. This is when the pic1650 belonged to General Instruments and they refer to it as a "programmable intelligent computer".
No kidding Programmable intelligent computer..yeah I would have put that last on my list.... Thanks for the information, as far as Wiki, "don't believe anything you read and only half of what you see", or is it visa versa..lol